The d3-pawn is a strong \"PPP\" (passed protected pawn). The position is very unpleasant for White.
24. c2d3  24... c4d3 The d3-pawn can be protected easily, if necessary, by a bishop on f5. Meanwhile Black can play Nc4 or Na4. 25. f2f3  25... b6c4  26. d2c4 